... in CE config.. as Vo=Vcc-Ic Rc nw as Vcc is const. v cn say Vo is directly proportional 2 (-Ic Rc) so nw when d base voltage is increased Ib will inc. thus, Ic will inc. cuz Ic=beta Ib thus Ic Rc drop increases... as Vo is prop 2 -Ic Rc thus, Vo will decrease...thus d curve for d +ve half cycle in which Ib is increasing drawn in 180 deg phase showing Vo is dec. n vice versa 4 -ve half cycle... nw in CC... as d o/p is taken frm emitter... Vo= Ie Re so der's no -ve sign..n for d +ve cycle Ie will incr(dat's leakage current) as der's no-ve sign it'll b in phase wid i/p..hence no phase shift as leakage current doesnt incr. so much thus,d o/p voltage Ie Re doesnt inc much thus, d o/p doesnt amplify much thus dis config knwn as emiter follower... nw in CB,... d I/P is appiled at emitter n o/p is taken frm collector... so, 4 d +ve half cycle d Eb junc will b more FB thus causing incr. in Ib n thus, in Ic... so inc. in Ic causes inc. in o/p voltage..n during -ve half cycle d junc will b less FB so o/p voltage will b decreasing..hence der's no phase shift...
yes there is 180 phase shift. it can be seen in graphs.
Common emitter is the only transistor configuration that has an 180 degree phase difference between input and output. Common base and common collector outputs are in phase with the input.***********************************That is incorrect.The output of the common emitter is inverted, there is no phase shift.
no phase shift
The Class A common emitter BJT design has input on the base and output on the collector. This design is inverting, or 180 degrees phase shift.
180 degree phase shift
The amplifier whose output is inphase with it input means if we consider voltage amplification then there is zero phase shift in input and output
In common emitter amplifier circuit, input and output voltage are out of phase. When input voltage is increased then ib is increased, ic also increases so voltage drop across Rc is increased. However, increase in voltage across RC is in opposite sense. So, the phase difference between the input and the output voltages is 180 degrees.
The R-C oscillator is also called a phase shift oscillator because the R-C filter creates a phase shift from input to output. The feedback portion of the oscillator (an amplifier) then serves to pump energy back into the filter.
In a two stage RC coupled amplifier, the two transistors are identical and a common power supply is used. The input is provided to the first stage of the amplifier where it is amplified and this output is used as input for the second stage. This is amplied once again by the other transistor in the second stage and the final output is obtained. There will be a 180 degree phase shift after the first stage amplification which is nullified by the 180 degree phase shift of the second stage amplification.Thus, we obtain an output which is an amplified signal of the input and is in phase with the input signal.
If the input and output are expressed in volts, then negative gain means a 180° phase shift. If the ratio of output to input is expressed in dB, then negative gain means attenuation, i.e., less power out than power in.
In the common emitter configuration, a class A amplifier, an increase in base voltage (the input) leads to an increase in base-emitter current which leads to a proportionately larger increase in base collector current. That pulls the collector towards the emitter, which decreases the collector voltage. Since the collector is the output, this configuration is an inverting amplifier.
when the switch the emitter-base junection is an opnd circut and heance the value of input or base curent is zero.